Biomass treatment for hydrothermal hydrocatalytic conversion

ABSTRACT

A selective removal of metal and its anion species that are detrimental to subsequent hydrothermal hydrocatalytic conversion from the biomass feed prior to carrying out catalytic hydrogenation/hydrogenolysis/hydrodeoxygenation of the biomass in a manner that does not reduce the effectiveness of the hydrothermal hydrocatalytic treatment while minimizing the amount of water used in the process is provided.

The present application claims the benefit of pending U.S. ProvisionalPatent Application Ser. No. 61/917,393, filed Dec. 18, 2013, the entiredisclosure of which is hereby incorporated by reference.

FIELD OF THE INVENTION

The invention relates to treatment of biomass for the hydrothermalhydrocatalytic treatment in the production of higher hydrocarbonssuitable for use in transportation fuels and industrial chemicals frombiomass. More specifically, the invention relates to removal ofdetrimental species from the biomass for an effective biomasshydrothermal hydrocatalytic conversion.

BACKGROUND OF THE INVENTION

A significant amount of attention has been placed on developing newtechnologies for providing energy from resources other than fossilfuels. Biomass is a resource that shows promise as a fossil fuelalternative. As opposed to fossil fuel, biomass is also renewable.

Biomass may be useful as a source of renewable fuels. One type ofbiomass is plant biomass. Plant biomass is the most abundant source ofcarbohydrate in the world due to the lignocellulosic materials composingthe cell walls in higher plants. Plant cell walls are divided into twosections, primary cell walls and secondary cell walls. The primary cellwall provides structure for expanding cells and is composed of threemajor polysaccharides (cellulose, pectin, and hemicellulose) and onegroup of glycoproteins. The secondary cell wall, which is produced afterthe cell has finished growing, also contains polysaccharides and isstrengthened through polymeric lignin covalently cross-linked tohemicellulose. Hemicellulose and pectin are typically found inabundance, but cellulose is the predominant polysaccharide and the mostabundant source of carbohydrates. However, production of fuel fromcellulose poses a difficult technical problem. Some of the factors forthis difficulty are the physical density of lignocelluloses (like wood)that can make penetration of the biomass structure of lignocelluloseswith chemicals difficult and the chemical complexity of lignocellulosesthat lead to difficulty in breaking down the long chain polymericstructure of cellulose into carbohydrates that can be used to producefuel. Another factor for this difficulty is the nitrogen compounds andsulfur compounds contained in the biomass. The nitrogen and sulfurcompounds contained in the biomass can poison catalysts used insubsequent processing.

Most transportation vehicles require high power density provided byinternal combustion and/or propulsion engines. These engines requireclean burning fuels which are generally in liquid form or, to a lesserextent, compressed gases. Liquid fuels are more portable due to theirhigh energy density and their ability to be pumped, which makes handlingeasier.

Currently, bio-based feedstocks such as biomass provide the onlyrenewable alternative for liquid transportation fuel. Unfortunately, theprogress in developing new technologies for producing liquid biofuelshas been slow in developing, especially for liquid fuel products thatfit within the current infrastructure. Although a variety of fuels canbe produced from biomass resources, such as ethanol, methanol, andvegetable oil, and gaseous fuels, such as hydrogen and methane, thesefuels require either new distribution technologies and/or combustiontechnologies appropriate for their characteristics. The production ofsome of these fuels also tends to be expensive and raise questions withrespect to their net carbon savings. There is a need to directly processbiomass into liquid fuels, amenable to existing infrastructure.

Processing of biomass as feeds is challenged by the need to directlycouple biomass hydrolysis to release sugars, and catalytichydrogenation/hydrogenolysis/hydrodeoxygenation of the sugar, to preventdecomposition to heavy ends (caramel, or tars). Further, it is achallenge to minimize generation of waste products that may requiretreating before disposal and/or catalyst deactivation by poisons.

SUMMARY OF THE INVENTION

It was found desirable to remove detrimental species from the biomassfeed prior to carrying out catalytichydrogenation/hydrogenolysis/hydrodeoxygenation of the biomass in amanner that does not reduce the effectiveness of the hydrothermalhydrocatalytic treatment while minimizing the amount of water used inthe process.

In one embodiment, a method is provided for selective removal of atleast a portion of detrimental metals and their anions (“detrimentalspecies”) from a detrimental species-containing cellulosic biomasssolids comprising:

-   -   a. providing a first portion of cellulosic biomass solids being        contacted by a first dispersed or semi-continuous liquid phase        and first continuous gas phase at a temperature in the range of        about 0° C. to about 60° C. in a first contact zone wherein the        liquid phase comprises acid solution having a pH of at most 4        wherein the flux of the first liquid phase is at least 1        kg/(m²s);    -   b. providing said first dispersed or semi-continuous liquid        phase treated cellulosic biomass solids being contacted by a        second dispersed or semi-continuous liquid phase and second        continuous gas phase at a temperature in the range of about        0° C. to about 60° C. in a second contact zone wherein the        liquid phase comprises an aqueous solution having a pH of at        least 5 wherein the flux of the second liquid phase is at least        1 kg/(m²s);    -   c. removing the first dispersed or semi-continuous liquid phase        from the first contact zone as an acidic effluent;    -   d. recovering the second dispersed or semi-continuous liquid        phase from the second contact zone as aqueous effluent;    -   e. recycling at least a portion of the aqueous effluent as a        portion of the liquid phase in the first contact zone;    -   f. transferring at least a portion of said second dispersed or        semi-continuous liquid phase treated cellulosic biomass solids        to a digestion and/or reaction zone.

In another embodiment, a method is provided for selective removal of atleast a portion of detrimental metals and their anions from adetrimental species-containing cellulosic biomass solids comprising:

-   -   a. providing a first portion of cellulosic biomass solids being        contacted by a first dispersed or semi-continuous liquid phase        and first continuous gas phase at a temperature in the range of        about 0° C. to about 60° C. in a first contact zone wherein the        liquid phase comprises acid solution having a pH of at most 4        wherein the flux of the first liquid phase is at least 1        kg/(m²s);    -   b. providing said first dispersed or semi-continuous liquid        phase treated cellulosic biomass solids being contacted by a        second dispersed or semi-continuous liquid phase and second        continuous gas phase at a temperature in the range of about        0° C. to about 60° C. in a second contact zone wherein the        liquid phase comprises an aqueous solution having a pH of at        least 5 wherein the flux of the second liquid phase is at least        1 kg/(m²s);    -   c. providing said second dispersed or semi-continuous liquid        phase treated cellulosic biomass solids being contacted by a        third dispersed or semi-continuous liquid phase and third        continuous gas phase at a temperature in the range of about        0° C. to about 60° C. in a third contact zone wherein the third        liquid phase comprises base solution having a pH of greater than        9 wherein the flux of the third liquid phase is at least 1        kg/(m²s);    -   d. providing said third dispersed or semi-continuous liquid        phase treated cellulosic biomass being contacted by a fourth        dispersed or semi-continuous liquid phase and fourth continuous        gas phase at a temperature in the range of about 0° C. to about        60° C. in a fourth contact zone wherein the liquid phase        comprises an aqueous solution having a pH of at most 8 wherein        the flux of the fourth liquid phase is at least 1 kg/(m²s);    -   e. removing the first dispersed or semi-continuous liquid phase        from the first contact zone as an acidic effluent;    -   f. recovering the second dispersed or semi-continuous liquid        phase from the second contact zone as first aqueous effluent;    -   g. removing the third dispersed or semi-continuous liquid phase        from the third contact zone as a basic effluent;    -   h. recovering the fourth dispersed or semi-continuous liquid        phase from the fourth contact zone as second aqueous effluent;    -   i. recycling at least a portion of the first aqueous effluent as        a portion of the liquid phase in the first contact zone;    -   j. recycling at least a portion of the second aqueous effluent        as a portion of the liquid phase in the third contact zone;    -   k. transferring at least a portion of said fourth dispersed or        semi-continuous liquid phase treated cellulosic biomass solids        to a digestion and/or reaction zone.

Yet in another embodiment, a method is provided for selective removal ofat least a portion of detrimental metals and their anions from adetrimental species-containing cellulosic biomass solids comprising:

-   -   a. providing a first portion of cellulosic biomass solids being        contacted by a first dispersed or semi-continuous liquid phase        and first continuous gas phase at a temperature in the range of        about 0° C. to about 60° C. in a first contact zone wherein the        liquid phase comprises a base solution having a pH of greater        than 9 wherein the flux of the first liquid phase is at least 1        kg/(m²s);    -   b. providing said first dispersed or semi-continuous liquid        phase treated cellulosic biomass solids being contacted by a        second dispersed or semi-continuous liquid phase and second        continuous gas phase at a temperature in the range of about        0° C. to about 60° C. in a second contact zone wherein the        liquid phase comprises an aqueous solution having a pH of at        most 8 wherein the flux of the second liquid phase is at least 1        kg/(m²s);    -   c. providing said second dispersed or semi-continuous liquid        phase treated cellulosic biomass solids being contacted by a        third dispersed or semi-continuous liquid phase and third        continuous gas phase at a temperature in the range of about        0° C. to about 60° C. in a third contact zone wherein the third        liquid phase comprises an acid solution having a pH of at most 4        wherein the flux of the third liquid phase is at least 1        kg/(m²s);    -   d. providing said third dispersed or semi-continuous liquid        phase treated cellulosic biomass being contacted by a fourth        dispersed or semi-continuous liquid phase and fourth continuous        gas phase at a temperature in the range of about 0° C. to about        60° C. in a fourth contact zone wherein the liquid phase        comprises an aqueous solution having a pH of at least 5 wherein        the flux of the fourth liquid phase is at least 1 kg/(m²s);    -   e. removing the first dispersed or semi-continuous liquid phase        from the first contact zone as an basic effluent;    -   f. recovering the second dispersed or semi-continuous liquid        phase from the second contact zone as first aqueous effluent;    -   g. removing the third dispersed or semi-continuous liquid phase        from the third contact zone as an acidic effluent;    -   h. recovering the fourth dispersed or semi-continuous liquid        phase from the fourth contact zone as second aqueous effluent;    -   i. recycling at least a portion of the first aqueous effluent as        a portion of the liquid phase in the first contact zone;    -   j. recycling at least a portion of the second aqueous effluent        as a portion of the liquid phase in the third contact zone;    -   k. transferring at least a portion of said fourth dispersed or        semi-continuous liquid phase treated cellulosic biomass solids        to a digestion and/or reaction zone.

In yet another embodiment, in the digestion and/or reaction zone of theabove methods, the treated cellulosic biomass is contacted with ahydrothermal hydrocatalytic catalyst in the presence of hydrogen and adigestion solvent thereby producing an intermediate oxygenated productstream comprising oxygenated hydrocarbons and water; and at least aportion of the water is separated and recycled to form at least aportion of the aqueous solution.

In yet another embodiment, in the digestion and/or reaction zone in theabove methods, the treated cellulosic biomass is contacted with ahydrothermal hydrocatalytic catalyst in the presence of hydrogen and adigestion solvent thereby producing an intermediate oxygenated productstream; at least a portion of the oxygenated intermediate product streamis converted to a hydrocarbon product stream comprising hydrocarbons andwater; and at least a portion of the water is separated and recycled toform at least a portion of the aqueous solution. The oxygenatedintermediate product steam may comprise oxygenated hydrocarbons andwater, and at least a portion of the water maybe separated and recycledto form at least a portion of the aqueous solution.

The features and advantages of the invention will be apparent to thoseskilled in the art. While numerous changes may be made by those skilledin the art, such changes are within the spirit of the invention.

BRIEF DESCRIPTION OF THE DRAWING

This drawing illustrates certain aspects of some of the embodiments ofthe invention, and should not be used to limit or define the invention.

FIG. 1 is a schematically illustrated block flow diagram of anembodiment of a process of this invention.

FIG. 2 is a schematically illustrated block flow diagram of anembodiment of a process of this invention.

FIG. 3 is a schematically illustrated block flow diagram of anembodiment of a process of this invention.

FIG. 4 is a schematically illustrated block flow diagram of anembodiment of a process of this invention.

DETAILED DESCRIPTION OF THE INVENTION

In one embodiment, the invention relates to selective removal ofdetrimental metals and their anions, such as chlorine, from detrimentalspecies-containing cellulosic biomass solids. Any suitable (e.g.,inexpensive and/or readily available) type of lignocellulosic biomasscan be used. Suitable lignocellulosic biomass can be, for example,selected from, but not limited to, wood, forestry residues, agriculturalresidues, herbaceous material, municipal solid wastes, pulp and papermill residues, and combinations thereof. Thus, in some embodiments, thebiomass can comprise, for example, corn stover, straw, bagasse,miscanthus, sorghum residue, switch grass, duckweed, bamboo, waterhyacinth, hardwood, hardwood chips, hardwood pulp, softwood, softwoodchips, softwood pulp, and/or combination of these feedstocks. Thebiomass can be chosen based upon a consideration such as, but notlimited to, cellulose and/or hemicelluloses content, lignin content,growing time/season, growing location/transportation cost, growingcosts, harvesting costs and the like. These cellulosic biomass solidscontain metal species and its corresponding anions such as Mg, Ca, Na, KFe, Mn, Cl, SO₄, PO₄, NO₃ that are detrimental to catalysts or equipmentused in the hydrothermal hydrocatalytic treatment of the biomass(“detrimental species”). Hence, it is desirable to at least in partremove these detrimental species from the cellulosic biomass solidsbefore the hydrothermal hydrocatalytic treatment of biomass.

The oxygenated hydrocarbons produced from the hydrothermalhydrocatalytic process are useful in the production of higherhydrocarbons suitable for use in transportation fuels and industrialchemicals from biomass. The higher hydrocarbons produced are useful informing transportation fuels, such as synthetic gasoline, diesel fuel,and jet fuel, as well as industrial chemicals. As used herein, the term“higher hydrocarbons” refers to hydrocarbons having an oxygen to carbonratio less than the oxygen to carbon ratio of at least one component ofthe biomass feedstock. As used herein the term “hydrocarbon” refers toan organic compound comprising primarily hydrogen and carbon atoms,which is also an unsubstituted hydrocarbon. In certain embodiments, thehydrocarbons of the invention also comprise heteroatoms (i.e., oxygensulfur, phosphorus, or nitrogen) and thus the term “hydrocarbon” mayalso include substituted hydrocarbons. As used herein, the term “solublecarbohydrates” refers to monosaccharides or polysaccharides that becomesolubilized in a digestion process.

Although the underlying chemistry is understood behind digestingcellulose and other complex carbohydrates and further transformingsimple carbohydrates into organic compounds reminiscent of those presentin fossil fuels, high-yield and energy-efficient digestion processessuitable for converting cellulosic biomass into fuel blends have yet tobe developed. In this regard, the most basic requirement associated withconverting cellulosic biomass into fuel blends using digestion and otherprocesses is that the energy input needed to bring about the conversionshould not be greater than the available energy output of the productfuel blends. Further the process should maximize product yield whileminimizing waste products. These basic requirements lead to a number ofsecondary issues that collectively present an immense engineeringchallenge that has not been solved heretofore.

Further, the removal of these detrimental species is complicated by thesensitivity of the catalysts for the hydrothermal hydrocatalytictreatment to the reaction conditions. Processing of biomass as feeds ischallenged by the need to directly couple biomass hydrolysis to releasesugars, and catalytic hydrogenation/hydrogenolysis/hydrodeoxygenation ofthe sugar, to prevent decomposition to heavy ends (caramel, or tars).For example, too much water from a wash process can dilute the reactionstream and require removal of larger amounts of water from the processand may further lead to stress on the catalyst used in the process.Further, removal of water at a later stage by thermally separating thewater will require a large amount of energy. It is also desirable torecycle the wash water to minimize or eliminate the need for other waterinputs to the process.

In further embodiment, the invention relates recycling the water used towash the biomass and to minimizing the amount of waste water generatedin the process. The invention balances the competing advantage ofselective removal of detrimental metal species and its anion, such aschlorine, from a detrimental species-containing cellulosic biomasssolids while not reducing the effectiveness of the hydrothermalhydrocatalytic treatment while minimizing the amount of water used inthe process. Applicants have found that washing the biomass with acids(mild acidic conditions) at low temperature effectively removes at leasta portion of the detrimental species in the biomass without removal ofcarbohydrates. However a large amount of water required to remove thedetrimental species also hinders and/or creates more process water thatrequires more water removal and disposals. The process of the inventionprovides effective solutions to these problems.

It is also important in the wash process to prevent the hydrolysis ofwood and loss of carbohydrate to the wash effluent (or aqueous solutioneffluent). Thus it is preferable to maintain the treatment of thebiomass to at most about 60° C. The loss of carbohydrate is preferablyless than 10% by weight, more preferably less than 5% by weight, evenmore preferably less than 2% by weight based on the carbohydratespresent in the biomass (dry basis).

Prior to treatment, the untreated biomass can be reduced in size (e.g.,chopping, crushing or debarking) to a convenient size and certainquality that aids in moving the biomass or mixing and impregnating thechemicals from digestive solvent. Thus, in some embodiments, providingbiomass can comprise harvesting a lignocelluloses-containing plant suchas, for example, a hardwood or softwood tree. The tree can be subjectedto debarking, chopping to wood chips of desirable thickness, and washingto remove any residual soil, dirt and the like.

It is preferable to render the biomass feed (wood chips or other) freeof entrained air, and densified to insure the feedstock will sink inwater or solvent, vs. float (pre-conditioning). Floating can occur ifthe feed is allowed to dry during storage, upon which air may enterpores and be transported into the process.

Densification via impregnation with water or solvent may be effected bysoaking in water or solvent. Pressurization of the water or solvent willforce liquid into pores. One of the most effective ways to drive gas(air or non-condensibles) out of the pore of the biomass is to contactthe biomass with solvent vapor, most preferable water vapor or steam.

Typically, this is done by supplying low pressure steam (nominal 1-2atmospheres above ambient pressure) to the bottom of a storage bin, andallowing the steam or solvent vapor to travel upwards through the bin ofsolids, to drive out air or entrained gas. Contacting of water orsolvent vapor at a temperature above the biomass temperature results incondensation of liquid water or vapor in the pores of the biomass,driving gas out of the pores. This saturates and densifies the biomasssuch that it now has a density greater than water or solvent, andtherefore sinks when added to liquid water or solvent during the washprocess.

The time and duration of the steaming should be controlled such that thetemperature of the biomass does not exceed about 60 degrees centigradefor an extended period of time. Specifically, one can supply steam attemperatures above 100 degrees centigrade (the boiling point of water),to biomass initially at ambient temperature (below about 35 degreescentigrade), for a period of time such that the final temperature of thebiomass does not exceed about 60 degrees centigrade, or if temperatureabove 60 degree centigrade, the exposure at this temperature is limitedto less than 60 minutes, preferably less than 30 minutes, and mostpreferably less than about 10 minutes. By minimizing the exposure totemperatures above 60° C., hydrolysis and degradation of carbohydratecomponents is minimized, and loss of these components to the waterand/or acid and base wash process steps can be minimized to less than 5%of the carbohydrate portion of the biomass, most preferably less than1%.

In one embodiment of the process, the detrimental species-containingcellulosic biomass solids is contacted by a first dispersed orsemi-continuous liquid phase and first continuous gas phase at atemperature in the range of about 0° C. to about 60° C., preferably inthe range of 10 to 45° C., in a first contact zone, wherein the flux ofthe first liquid phase is at least 1 kg/(m²s), preferably at least 3kg/(m²s), producing first dispersed or semi-continuous liquid phasetreated cellulosic biomass solids and a liquid effluent. In oneembodiment, the liquid phase in the first contact zone contains an acidsolution having a pH of at most 4, preferably having a pH of at least 0,more preferably having a pH in the range of 0 to 3, and the liquideffluent is an acidic effluent.

The acidic solution may contain an inorganic acid or carboxylic acid(“collectively referred herein as “acids”). The inorganic acid may be,for example, sulfuric acid, phosphoric acid, hydrochloric acid, nitricacid or mixtures thereof. The acid content of the acidic solution ispreferably less than 10 wt % and at least 0.01 wt %. The inorganic acidis preferably present in an amount of 0.01 wt % to 2 wt %. If sulfuricacid is used, the sulfuric acid is preferably present in an amount of0.01 wt % to 1 wt %. If phosphoric acid is used, the phosphoric acid ispreferably present in an amount of 0.01 wt % to 2 wt %. If nitric acidis used, the nitric acid is preferably present in an amount of 0.01 wt %to 1 wt %. The carboxylic acid may be, for example, acetic acid,levulinic acid, lactic acid, formic acid, propionic acid, or mixturesthereof. The carboxylic acid is preferably present in an amount of 0.1wt % to 5 wt %. If acetic acid is used, the acetic acid is preferablypresent in an amount of 0.1 wt % to 2.5 wt %.

The first dispersed or semi-continuous liquid phase treated cellulosicbiomass solids is contacted by a second dispersed or semi-continuousliquid phase and second continuous gas phase at a temperature in therange of about 0° C. to about 60° C., preferably in the range of 10 to45° C., in a second contact zone, wherein the flux of the first liquidphase is at least 1 kg/(m²s), preferably at least 3 kg/(m²s), producingsecond dispersed or semi-continuous liquid phase treated cellulosicbiomass solids and a second liquid effluent. In one embodiment, theliquid phase in the second contact zone is an aqueous solution having apH of at least 5, and the liquid effluent is an aqueous effluent. Thesecond dispersed or semi-continuous liquid phase treated cellulosicbiomass solids have reduced detrimental-species content compared to thedetrimental species-containing cellulosic biomass solids.

The first contact zone and the second contact zone are in communicationsuch that the cellulosic biomass solids from the first contact zone arecarried forward to the second contact zone. The first contact zone andthe second contact zone may be in one vessel or in separate vessels aslong as they are in communication. In one embodiment, both first liquidphase and second liquid phase flow downward. In another embodiment, thefirst gas phase is static gas blanket to maintain pressure. In anotherembodiment, the second gas phase is static gas blanket to maintainpressure. In other embodiments, the first gas phase may flowconcurrently or counter-currently with the first liquid phase. In otherembodiments, the second gas phase may flow concurrently orcounter-currently with the second liquid phase. In an embodiment, thebiomass and the liquid phase may flow co-currently or counter currently.The first gas phase and the second gas phase may be different or thesame. The gas phase may be air or any mixture of gases, such asnitrogen, argon, carbon dioxide, steam, or natural gas.

The first dispersed or semi-continuous liquid phase is preferablyrecycled at least one time through the first contact zone to increaseresidence time for treatment, to effect multiple passes through thebiomass being treated. The second dispersed or semi-continuous liquidphase is preferably recycled at least one time through the secondcontact zone to increase residence time for treatment, to effectmultiple passes through the biomass being treated. At least a portion ofthe separated aqueous effluent can be recycled to the second contactzone to form at least a portion of the aqueous solution.

In another embodiment, optionally, the second dispersed orsemi-continuous liquid phase treated cellulosic biomass solids (waterwashed cellulosic biomass solids) can be further washed by a basesolution. The water washed cellulosic biomass solids can be optionallycontacted by a third dispersed or semi-continuous liquid phase and thirdcontinuous gas phase at a temperature in the range of about 0° C. toabout 60° C., preferably in the range of 10 to 45° C., in a thirdcontact zone, wherein the flux of the third liquid phase is at least 1kg/(m²s), preferably at least 3 kg/(m²s), producing third dispersed orsemi-continuous liquid phase treated cellulosic biomass solids and aliquid effluent. In one embodiment, the liquid phase in the thirdcontact zone contains a base solution having a pH of greater than 9,preferably having a pH of at least 10, having a pH of at most 13, morepreferably having a pH in the range of 10 to 13, and the liquid effluentis a basic effluent.

The base solution may contain an inorganic base such as, for example,KOH, NaOH and ammonia. The base content of the base solution ispreferably less than 5 Normal and at least 0.01 Normal. The baseconcentration is preferably from about 0.1 to about 5 Normal.

The third dispersed or semi-continuous liquid phase treated cellulosicbiomass solids is contacted by a fourth dispersed or semi-continuousliquid phase and fourth continuous gas phase at a temperature in therange of about 0° C. to about 60° C., preferably in the range of 10 to45° C., in a fourth contact zone, wherein the flux of the first liquidphase is at least 1 kg/(m²s), preferably at least 3 kg/(m²s), producingfourth dispersed or semi-continuous liquid phase treated cellulosicbiomass solids and a fourth liquid effluent. In one embodiment, theliquid phase in the fourth contact zone is an aqueous solution having apH of at most 8, and the liquid effluent is an aqueous effluent. Thefourth dispersed or semi-continuous liquid phase treated cellulosicbiomass solids have reduced detrimental-species content compared to thedetrimental species-containing cellulosic biomass solids.

The third dispersed or semi-continuous liquid phase is preferablyrecycled at least one time through the third contact zone to increaseresidence time for treatment, to effect multiple passes through thebiomass being treated. The fourth dispersed or semi-continuous liquidphase is preferably recycled at least one time through the fourthcontact zone to increase residence time for treatment, to effectmultiple passes through the biomass being treated.

Preferably, the metal species content is reduced by at least 75%, atleast 80%, at least 85%, at least 90%, at least 95%, even at least 98%or essentially completely. More particularly the non-water solublemetals such as manganese is reduced by at least 20%, at least 30%, atleast 35%, at least 40%, at least 50%, at least 60%, at least 70%, atleast 75%, at least 80%, at least 90%, at least 95%, or essentiallycompletely. Preferably the anion content such as chlorine is alsoreduced by at least 50%, at least 55%, at least 60%, at least 75%, evenat least 95%. The term “essentially completely” means the specie iscompletely removed within the detection limit or within statisticalsignificance or within measurement errors.

The second contact zone and the third contact zone, if any, are incommunication such that the cellulosic biomass solids from the secondcontact zone are carried forward to the third contact zone. The thirdcontact zone and the fourth contact zone, if any, are in communicationsuch that the cellulosic biomass solids from the third contact zone arecarried forward to the fourth contact zone. The third contact zone andthe fourth contact zone may be in one vessel or in separate vessels aslong as they are in communication. In one embodiment, both third liquidphase and fourth liquid phase flow downward. In another embodiment, thethird gas phase is static gas blanket to maintain pressure. In anotherembodiment, the fourth gas phase is static gas blanket to maintainpressure. In other embodiments, the third gas phase may flowconcurrently or counter-currently with the third liquid phase. In otherembodiments, the fourth gas phase may flow concurrently orcounter-currently with the fourth liquid phase. In an embodiment, thebiomass and the liquid phase may flow co-currently or counter currently.The third gas phase and the fourth gas phase may be different or thesame. The gas phase may be air or any mixture of gases, such as nitrogenargon, carbon dioxide, steam, or natural gas.

In another embodiment, the acidic solution and the base solution can bereversed in order where the first dispersed or semi-continuous liquidphase can be the base solution and the third dispersed andsemi-continuous liquid phase can be the acidic solution.

The use of trickle flow system for washing and use of recycle treatmentwater, as described in the present invention, is effective to produce aneffluent separated from the biomass which contains a maximumconcentrations of the detrimental removed components, in the restrictedamounts of water treatment allowed. The amounts of water prescribed willtypically correspond to the natural water content of the biomassfeedstock, augmented by any water which can be made in processconversion steps such as reaction of biomass with hydrogen, with zero orminimal use of additional water from another source. The amount ofadditional water required is thus restricted to less than 50% of thebiomass feed (dry basis), and hence would represent less than a third ofthe typical amount of additional water employed for similar processingin the manufacture of, for example, pulp used to make paper. Preferably,the amount of additional makeup water above the water naturally presentin the biomass feed, and made in the process, is negligible or zero.

The pretreatment wash process is carried out so that the amount of theeffluent (from both acidic effluent and basic effluent) is in the rangeof about 3 parts to about 0.5 parts, preferably in the range of about 2parts to about 1 part relative to the cellulosic biomass solids (drybasis) charged to the treatment step, based on weight. The treatedcellulosic biomass solids are then transferred to a digestion and/orreaction zone.

Yet in another embodiment, a gas and/or an organic solvent may be passedthrough the second dispersed or semi-continuous liquid phase treatedcellulosic biomass (or fourth dispersed or semi-continuous liquid phasetreated cellulosic biomass) to produce an aqueous effluent and apretreated cellulosic biomass solids with reduced water content comparedto the aqueous solution treated biomass solids prior to transferring thetreated biomass to a digestion and/or reaction zone. In yet anotherembodiment, a gas and/or an organic solvent may be passed through thefourth dispersed or semi-continuous liquid phase treated cellulosicbiomass to produce an aqueous effluent and a pretreated cellulosicbiomass solids with reduced water content compared to the aqueoussolution treated biomass solids prior to transferring the treatedbiomass to a digestion and/or reaction zone. The organic solvent maycontain water. At least a portion of the treated cellulosic biomasssolids is provided to a digestion and/or reaction zone (collectivelyreferred to as “hydrothermal hydrocatalytic reaction zone”) for furtherprocessing. This zone may be conducted in a single step or in multiplesteps or vessels as described below.

In reference to FIG. 1, in one embodiment of the invention process,detrimental species-containing cellulosic biomass solids 2 is introducedinto a first contact zone 10. The detrimental species-containingcellulosic biomass solids is contacted, in the first contact zone 10, bya first dispersed or semi-continuous liquid phase 6 in the presence offirst continuous gas phase 5 at a temperature in the range of about 0°C. to about 60° C., wherein the flux of the first liquid phase is atleast 1 kg/(m²s), producing first dispersed or semi-continuous liquidphase treated cellulosic biomass solids 16 and a first liquid effluent12 and a gas effluent 8. The liquid phase may be recycled via conduit 7.The gas phase may be optionally provided 15 to the second contact zoneor may be optionally recycled within the first contact zone (not shown).In one embodiment, the cellulosic biomass solids, liquid phase, and thegas phase are flowing co-currently. The first dispersed orsemi-continuous liquid phase 6 is an acidic solution and the firstliquid effluent 12 is an acidic effluent containing the detrimentalspecies acid washed from the detrimental species-containing cellulosicbiomass solids. The first dispersed or semi-continuous liquid phasetreated cellulosic biomass solids 16 have reduced detrimental-speciescontent compared to the detrimental species-containing cellulosicbiomass solids 2.

The first dispersed or semi-continuous liquid phase treated cellulosicbiomass solids 16 is contacted by a second dispersed or semi-continuousliquid phase 24 and second continuous gas phase 15 at a temperature inthe range of about 0° C. to about 60° C., in a second contact zone 20,wherein the flux of the first liquid phase is at least 1 kg/(m²s),producing second dispersed or semi-continuous liquid phase treatedcellulosic biomass solids 2, a gas effluent 28, and a second liquideffluent 22. In one embodiment, the liquid phase 24 is an aqueoussolution having a pH of at least 5, and the liquid effluent 22 is anaqueous effluent. The liquid phase may be recycled via conduit 25. Thesecond dispersed or semi-continuous liquid phase treated cellulosicbiomass solids 26 have reduced detrimental-species content compared tothe detrimental species-containing cellulosic biomass solids. At least aportion of the separated aqueous effluent 22 can be recycled to thefirst contact zone to form at least a portion of the first dispersed orsemi-continuous liquid phase 6.

In reference to FIG. 2, in one embodiment of the invention process,detrimental species-containing cellulosic biomass solids 102 isintroduced into a first contact zone 100. The detrimentalspecies-containing cellulosic biomass solids is contacted, in the firstcontact zone 100, by a first dispersed or semi-continuous liquid phase106 in the presence of first continuous gas phase 105 at a temperaturein the range of about 0° C. to about 60° C., wherein the flux of thefirst liquid phase is at least 1 kg/(m²s), producing first dispersed orsemi-continuous liquid phase treated cellulosic biomass solids 116, agas effluent 108, and a first liquid effluent 112 and a gas effluent108. The liquid phase may be recycled via conduit 107. In oneembodiment, the cellulosic biomass solids, liquid phase, and the gasphase are flowing counter-currently. The first dispersed orsemi-continuous liquid phase 106 is an acidic solution and the firstliquid effluent 112 is an acidic effluent containing the detrimentalspecies acid washed from the detrimental species-containing cellulosicbiomass solids. The first dispersed or semi-continuous liquid phasetreated cellulosic biomass solids 116 have reduced detrimental-speciescontent compared to the detrimental species-containing cellulosicbiomass solids 102.

The first dispersed or semi-continuous liquid phase treated cellulosicbiomass solids 116 is contacted by a second dispersed or semi-continuousliquid phase 224 and second continuous gas phase 205 at a temperature inthe range of about 0° C. to about 60° C., in a second contact zone 200,wherein the flux of the first liquid phase is at least 1 kg/(m²s),producing second dispersed or semi-continuous liquid phase treatedcellulosic biomass solids 226, a gas effluent 208, and a second liquideffluent 122. In one embodiment, the liquid phase 224 is an aqueoussolution having a pH of at least 5, and the liquid effluent 122 is anaqueous effluent. The liquid phase may be recycled via conduit 225. Inone embodiment, the cellulosic biomass solids, liquid phase, and the gasphase are flowing counter-currently. The second dispersed orsemi-continuous liquid phase treated cellulosic biomass solids 226 havereduced detrimental-species content compared to the detrimentalspecies-containing cellulosic biomass solids. At least a portion of theseparated aqueous effluent 122 can be recycled to the first contact zoneto form at least a portion of the first dispersed or semi-continuousliquid phase 106. The gas effluent 208 from the gas phase in the secondcontact zone may be optionally provided to 105 to the first contact zoneas the gas phase.

In reference to FIG. 3, in one embodiment of the invention process,detrimental species-containing cellulosic biomass solids 502 isintroduced into a first contact zone 500. The detrimentalspecies-containing cellulosic biomass solids is contacted, in the firstcontact zone 500, by a first dispersed or semi-continuous liquid phase506 in the presence of first continuous gas phase 505 at a temperaturein the range of about 0° C. to about 60° C., wherein the flux of thefirst liquid phase is at least 1 kg/(m²s), producing first dispersed orsemi-continuous liquid phase treated cellulosic biomass solids 516, anda first liquid effluent 522. The liquid phase may be recycled viaconduit (not shown). In one embodiment, the gas phase, the liquid phase,and cellulosic biomass solids are flowing counter-currently. The firstdispersed or semi-continuous liquid phase 506 in counter-current flow tothe biomass 502 is an acidic solution and the first liquid effluent 522is an acidic effluent containing the detrimental species acid washedfrom the detrimental species-containing cellulosic biomass solids. Thefirst dispersed or semi-continuous liquid phase treated cellulosicbiomass solids 516 have reduced detrimental-species content compared tothe detrimental species-containing cellulosic biomass solids 502.

The first dispersed or semi-continuous liquid phase treated cellulosicbiomass solids 516 is contacted by a second dispersed or semi-continuousliquid phase 624 and second continuous gas phase (that may be the sameas the first continuous gas phase) at a temperature in the range ofabout 0° C. to about 60° C., in a second contact zone 600, wherein theflux of the second liquid phase is at least 1 kg/(m²s), producing seconddispersed or semi-continuous liquid phase treated cellulosic biomasssolids 626, a gas effluent 608, and a second liquid effluent 612. In oneembodiment, the liquid phase 624 is an aqueous solution having a pH ofat least 5, and the liquid effluent 612 is an aqueous effluent. At leasta portion of the aqueous effluent 612 may be acidified by an acid or adilute acid 504 to produce first dispersed or semi-continuous liquidphase 506. The liquid phase may be recycled via conduit (not shown). Inone embodiment, the gas phase, the liquid phase, and cellulosic biomasssolids are flowing counter-currently. The second dispersed orsemi-continuous liquid phase treated cellulosic biomass solids 626 havereduced detrimental-species content compared to the detrimentalspecies-containing cellulosic biomass solids.

In reference to FIG. 4, in one embodiment of the invention process,detrimental species-containing cellulosic biomass solids 802 isintroduced into a first contact zone 800. The detrimentalspecies-containing cellulosic biomass solids is contacted, in the firstcontact zone 800, by a first dispersed or semi-continuous liquid phase806 in the presence of first continuous gas phase 805 at a temperaturein the range of about 0° C. to about 60° C., wherein the flux of thefirst liquid phase is at least 1 kg/(m²s), producing first dispersed orsemi-continuous liquid phase treated cellulosic biomass solids 816 and afirst liquid effluent 812 and a gas effluent 808. The liquid phase maybe recycled via conduit 807. The gas phase may be optionally provided815 to the second contact zone or may be optionally recycled within thefirst contact zone (not shown). In one embodiment, the cellulosicbiomass solids, liquid phase, and the gas phase are flowingco-currently. In one embodiment, the first dispersed or semi-continuousliquid phase 806 is an acidic solution and the first liquid effluent 812is an acidic effluent containing the detrimental species acid washedfrom the detrimental species-containing cellulosic biomass solids. Inanother embodiment, the first dispersed or semi-continuous liquid phase806 is a base solution and the first liquid effluent 812 is a basiceffluent containing the detrimental species acid washed from thedetrimental species-containing cellulosic biomass solids. The firstdispersed or semi-continuous liquid phase treated cellulosic biomasssolids 816 have reduced detrimental-species content compared to thedetrimental species-containing cellulosic biomass solids 802.

The first dispersed or semi-continuous liquid phase treated cellulosicbiomass solids 816 is contacted by a second dispersed or semi-continuousliquid phase 824 and second continuous gas phase 815 at a temperature inthe range of about 0° C. to about 60° C., in a second contact zone 850,wherein the flux of the second liquid phase is at least 1 kg/(m²s),producing second dispersed or semi-continuous liquid phase treatedcellulosic biomass solids 826, a gas effluent 828, and a second liquideffluent 822. In one embodiment, the liquid phase 824 is an aqueoussolution having a pH of at least 5, and the liquid effluent 822 is anaqueous effluent. The liquid phase may be recycled via conduit 825. Thesecond dispersed or semi-continuous liquid phase treated cellulosicbiomass solids 826 have reduced detrimental-species content compared tothe detrimental species-containing cellulosic biomass solids. At least aportion of the separated aqueous effluent 822 can be recycled to thefirst contact zone to form at least a portion of the first dispersed orsemi-continuous liquid phase 806 by addition of acid or acidic solution804 if 806 is an acidic solution or by addition of base or base solution804 if 806 is a base solution.

The second dispersed or semi-continuous liquid phase treated cellulosicbiomass solids 826 is contacted by a third dispersed or semi-continuousliquid phase 906 and third continuous gas phase 905 at a temperature inthe range of about 0° C. to about 60° C., in a third contact zone 900,wherein the flux of the third liquid phase is at least 1 kg/(m²s),producing third dispersed or semi-continuous liquid phase treatedcellulosic biomass solids 916, a gas effluent 908, and a third liquideffluent 912. The liquid phase may be recycled via conduit 907. The gasphase may be optionally provided 915 to the fourth contact zone or maybe optionally recycled within the third contact zone (not shown). In oneembodiment, the cellulosic biomass solids, liquid phase, and the gasphase are flowing co-currently. In one embodiment, if the firstdispersed or semi-liquid phase 806 is a base solution, the thirddispersed or semi-continuous liquid phase 906 is an acidic solution andthe third liquid effluent 912 is an acidic effluent containing thedetrimental species acid washed from the detrimental species-containingcellulosic biomass solids. In another embodiment, if the first dispersedor semi-liquid phase 806 is an acidic solution, the third dispersed orsemi-continuous liquid phase 906 is a base solution and the third liquideffluent 912 is a basic effluent containing the detrimental species acidwashed from the detrimental species-containing cellulosic biomasssolids. The third dispersed or semi-continuous liquid phase treatedcellulosic biomass solids 916 have reduced detrimental-species contentcompared to the detrimental species-containing cellulosic biomass solids816.

The third dispersed or semi-continuous liquid phase treated cellulosicbiomass solids 916 is contacted by a fourth dispersed or semi-continuousliquid phase 924 and fourth continuous gas phase 915 at a temperature inthe range of about 0° C. to about 60° C., in a fourth contact zone 950,wherein the flux of the fourth liquid phase is at least 1 kg/(m²s),producing fourth dispersed or semi-continuous liquid phase treatedcellulosic biomass solids 926, a gas effluent 928, and a fourth liquideffluent 922. In one embodiment, the liquid phase 924 is an aqueoussolution having a pH of at least 5, and the liquid effluent 922 is anaqueous effluent. The liquid phase may be recycled via conduit 925. Thefourth dispersed or semi-continuous liquid phase treated cellulosicbiomass solids 926 have reduced detrimental-species content compared tothe detrimental species-containing cellulosic biomass solids. At least aportion of the separated aqueous effluent 922 can be recycled to thefirst contact zone to form at least a portion of the first dispersed orsemi-continuous liquid phase 906 by addition of acid or acidic solution904 if 906 is an acidic solution or by addition of base or base solution904 if 906 is a base solution.

The pretreated cellulosic biomass is provided to digestion/reaction zone(“hydrothermal catalytic reaction zone”) that may have one or moreunits, that in at least one unit containing a hydrothermalhydrocatalytic catalyst that is capable of activating molecular hydrogento produce an intermediate oxygenated product stream containingoxygenated hydrocarbons and water in the presence of hydrogen. Water maybe removed, in a water separation zone, from the oxygenated hydrocarbonstream produced in the thermal catalytic zone and recycled to form atleast a portion of the aqueous solution. At least a portion of theoxygenated hydrocarbon stream may be converted in a conversion zone (notshown in Figures) to a hydrocarbon product stream comprisinghydrocarbons and water; and at least a portion of the water may beseparated and recycled to the aqueous contact zones to form at least aportion of the aqueous solution. Water may be separated from thehydrocarbon or from the oxygenated hydrocarbon stream by conventionalmethod including liquid/liquid separation, decanting, or flashing.

An optional rinse step may be deployed to displace the treatment waterfrom the bed. This rinse step may use fresh water, or solvent, and canbe continued until the composition of impurities in the liquid exitingthe bed is reduced to less than 25% of that found exiting in thetreatment liquor before the rinse step. The rinse step may employ water,or solvent.

A gas and/or an organic solvent may be passed through aqueous solutionwashed cellulosic biomass solids, preferably downwardly or horizontally,in yet another optional step to produce a pretreated cellulosic biomasssolids with reduced water content compared to the water washedcellulosic biomass solids and separated aqueous effluent. Such method isdescribed in a commonly owned patent application titled “BIOMASSPRETREATMENT FOR HYDROTHERMAL HYDROCATALYTIC CONVERSION” filedco-currently herewith, which disclosure is hereby incorporated byreference in its entirety. In the displacement step the water content isreduced by at least by 5%, preferably at least by 25%, more preferablyat least by 50% relative to the total amount of water retained in thebed prior to displacement. The water displacement step may be any methodof removing water effectively from the process, such as use of a gasphase to displace water, or use of miscible or immiscible solvent todisplace water. If a solvent is used to displace water, it is preferableto use the solvent or intermediates stream used in the process, so asnot to have to separate the solvent later.

Water may also be removed in part after the pretreatment steps, via useof multieffect drying with solvent, or thermal drying including use ofwaste heat in drying, or via compression drying wherein the biomass iscompressed to remove water, and expanded in presence of a gas or liquidphase with reduced water content.

The pretreated cellulosic biomass can be provided to adigestion/reaction zone (“hydrothermal catalytic reaction zone”) thatmay have one or more units, that in at least one unit containing ahydrothermal hydrocatalytic catalyst that is capable of activatingmolecular hydrogen to produce an intermediate oxygenated product streamcontaining oxygenated hydrocarbons and water in the presence ofhydrogen. Water may be removed, in a water separation zone, from theoxygenated hydrocarbon stream produced in the thermal catalytic zone andrecycled via a recycle conduit to form at least a portion of the aqueoussolution that can be recycled to either or both acid removal aqueousrinse step or base removal aqueous rinse step. At least a portion of theoxygenated hydrocarbon stream may be converted in a conversion zone (notshown in Figures) to a hydrocarbon product stream comprisinghydrocarbons and water; and at least a portion of the water may beseparated and recycled to the second contact zone, or, to form at leasta portion of the aqueous solution. Water may be separated from thehydrocarbon or from the oxygenated hydrocarbon stream by conventionalmethod including liquid/liquid separation, decanting, or flashing.

For the instant biofuels process, the minimization of fresh water usageis a key issue. However, due to biomass packing density being poor, atbest 3 parts or more of bed volume of water are required to typicallyfill a bed for washing one part of biomass. In the invention process,the detrimental species is removed with less than 5 parts, preferably atmost 2.5 parts, more preferably at most 2 parts, even at most 1.5 partsof water for washing one part of biomass. It is preferred that for theremoval process, only the water from the water in the biomass and watergenerated in the process

As indicated in the figures, the flow of biomass solids stream can be inco- and/or counter-current mode relative to the liquid stream (acidicsolution and aqueous solution) in each of the separate zones leading tovarious different combinations of flow arrangement of streams.

For the hydrothermal catalytic reaction zone, the zone may have one ormore vessels. In one embodiment in the digestion/reaction zonehydrolysis and hydrothermal hydrocatalytic reaction of the treatedbiomass is carried out in one or more vessels. These vessels may bedigesters or reactors or combination thereof including a combinationhydrothermal hydrocatalytic digestion unit.

In some embodiments, lignocellulosic biomass (solids) being continuouslyor semi-continuously added to the hydrothermal digestion unit orhydrothermal hydrocatalytic digestion unit may be pressurized beforebeing added to the unit, particularly when the hydrothermal(hydrocatalytic) digestion unit is in a pressurized state.Pressurization of the cellulosic biomass solids from atmosphericpressure to a pressurized state may take place in one or morepressurization zones before addition of the cellulosic biomass solids tothe hydrothermal (hydrocatalytic) digestion unit. Suitablepressurization zones that may be used for pressurizing and introducinglignocellulosic biomass to a pressurized hydrothermal digestion unit orhydrothermal hydrocatalytic digestion unit are described in more detailin commonly owned United States Patent Application PublicationsUS20130152457 and US20130152458, and incorporated herein by reference inits entirety. Suitable pressurization zones described therein mayinclude, for example, pressure vessels, pressurized screw feeders, andthe like. In some embodiments, multiple pressurization zones may beconnected in series to increase the pressure of the cellulosic biomasssolids in a stepwise manner. The digestion and the hydrothermalhydrocatalytic reaction in the hydrothermal catalytic reaction zone (ordigestion reaction zone) may be conducted separately, partiallycombined, or in situ.

In some embodiments, the digestion rate of cellulosic biomass solids maybe accelerated in the presence of a liquid phase containing a digestionsolvent. In some instances, the liquid phase may be maintained atelevated pressures that keep the digestion solvent in a liquid statewhen raised above its normal boiling point. Although the more rapiddigestion rate of cellulosic biomass solids under elevated temperatureand pressure conditions may be desirable from a throughput standpoint,soluble carbohydrates may be susceptible to degradation at elevatedtemperatures. One approach for addressing the degradation of solublecarbohydrates during hydrothermal digestion is to conduct an in situcatalytic reduction reaction process so as to convert the solublecarbohydrates into more stable compounds as soon as possible after theirformation.

In certain embodiments, a slurry catalyst may be effectively distributedfrom the bottom of a charge of cellulosic biomass solids to the topusing upwardly directed fluid flow to fluidize and upwardly conveyslurry catalyst particulates into the interstitial spaces within thecharge for adequate catalyst distribution within the digestingcellulosic biomass solids. Suitable techniques for using fluid flow todistribute a slurry catalyst within cellulosic biomass solids in such amanner are described in commonly owned United States Published PatentApplications US20140005445 and US20140005444, and incorporated herein byreference in its entirety. In addition to affecting distribution of theslurry catalyst, upwardly directed fluid flow may promote expansion ofthe cellulosic biomass solids and disfavor gravity-induced compactionthat occurs during their addition and digestion, particularly as thedigestion process proceeds and their structural integrity decreases.Methods of effectively distributing molecular hydrogen within cellulosicbiomass solids during hydrothermal digestion is further described incommonly owned United States Published Patent Applications US20140174433and US20140174432 and incorporated herein by reference in its entirety.

In another embodiment the hydrothermal hydrocatalytic digestion unit maybe configured as disclosed in a co-pending United States PublishedPatent Application US20140117276 which disclosure is hereby incorporatedby reference. In the digestion zone, the size-reduced biomass iscontacted with the digestive solvent where the digestion reaction takesplace. The digestive solvent must be effective to digest lignins.

In some embodiments, at least a portion of oxygenated hydrocarbonsproduced in the hydrothermal hydrocatalytic reaction zone are recycledwithin the process and system to at least in part from the in situgenerated solvent, which is used in the biomass digestion process.Further, by controlling the degradation of carbohydrate in thehydrothermal hydrocatalytic reaction (e.g., hydrogenolysis process),hydrogenation reactions can be conducted along with the hydrogenolysisreaction at temperatures ranging from about 150° C. to 300° C. As aresult, a separate hydrogenation reaction section can optionally beavoided, and the fuel forming potential of the biomass feedstock fed tothe process can be increased. Further, it may be advantageous to use thein situ generated solvent as the organic solvent in pretreatment.

In various embodiments, the fluid phase digestion medium in which thehydrothermal digestion and catalytic reduction reaction, in thehydrothermal hydrocatalytic reaction zone, are conducted may comprise anorganic solvent and water. Although any organic solvent that is at leastpartially miscible with water may be used as a digestion solvent,particularly advantageous organic solvents are those that can bedirectly converted into fuel blends and other materials without beingseparated from the alcoholic component being produced from thecellulosic biomass solids. That is, particularly advantageous organicsolvents are those that may be co-processed along with the alcoholiccomponent during downstream processing reactions into fuel blends andother materials. Suitable organic solvents in this regard may include,for example, ethanol, ethylene glycol, propylene glycol, glycerol,phenolics and any combination thereof. In situ generated organicsolvents are particularly desirable in this regard.

In some embodiments, the fluid phase digestion medium may comprisebetween about 1% water and about 99% water. Although higher percentagesof water may be more favorable from an environmental standpoint, higherquantities of organic solvent may more effectively promote hydrothermaldigestion due to the organic solvent's greater propensity to solubilizecarbohydrates and promote catalytic reduction of the solublecarbohydrates. In some embodiments, the fluid phase digestion medium maycomprise about 90% or less water by weight. In other embodiments, thefluid phase digestion medium may comprise about 80% or less water byweight, or about 70% or less water by weight, or about 60% or less waterby weight, or about 50% or less water by weight, or about 40% or lesswater by weight, or about 30% or less water by weight, or about 20% orless water by weight, or about 10% or less water by weight, or about 5%or less water by weight.

In some embodiments, catalysts capable of activating molecular hydrogenhydrothermal hydrocatalytic catalysts, which are capable of activatingmolecular hydrogen (e.g., hydrogenolysis catalyst) and conducting acatalytic reduction reaction may comprise a metal such as, for example,Cr, Mo, W, Re, Mn, Cu, Cd, Fe, Co, Ni, Pt, Pd, Rh, Ru, Ir, Os, andalloys or any combination thereof, either alone or with promoters suchas Au, Ag, Cr, Zn, Mn, Sn, Bi, B, O, and alloys or any combinationthereof. In some embodiments, the catalysts and promoters may allow forhydrogenation and hydrogenolysis reactions to occur at the same time orin succession of one another. In some embodiments, such catalysts mayalso comprise a carbonaceous pyropolymer catalyst containing transitionmetals (e.g., Cr, Mo, W, Re, Mn, Cu, and Cd) or Group VIII metals (e.g.,Fe, Co, Ni, Pt, Pd, Rh, Ru, Ir, and Os). In some embodiments, theforegoing catalysts may be combined with an alkaline earth metal oxideor adhered to a catalytically active support. In some or otherembodiments, the catalyst may be deposited on a catalyst support thatmay not itself be catalytically active.

In some embodiments, the hydrothermal hydrocatalytic catalyst maycomprise a slurry catalyst. In some embodiments, the slurry catalyst maycomprise a poison-tolerant catalyst. As used herein the term“poison-tolerant catalyst” refers to a catalyst that is capable ofactivating molecular hydrogen without needing to be regenerated orreplaced due to low catalytic activity for at least about 12 hours ofcontinuous operation. Use of a poison-tolerant catalyst may beparticularly desirable when reacting soluble carbohydrates derived fromcellulosic biomass solids that have not had catalyst poisons removedtherefrom. Catalysts that are not poison tolerant may also be used toachieve a similar result, but they may need to be regenerated orreplaced more frequently than does a poison-tolerant catalyst.

In some embodiments, suitable poison-tolerant catalysts may include, forexample, sulfided catalysts. In some or other embodiments, nitridedcatalysts may be used as poison-tolerant catalysts. Sulfided catalystssuitable for activating molecular hydrogen and buffers suitable for usewith such catalysts are described in commonly owned United States PatentApplication Publications US20120317872, US20130109896, andUS20120317873, and United States Patent Application, US20140166221, eachof which is incorporated herein by reference in its entirety. Sulfidingmay take place by treating the catalyst with hydrogen sulfide or analternative sulfiding agent, optionally while the catalyst is disposedon a solid support. In more particular embodiments, the poison-tolerantcatalyst may comprise (a) sulfur and (b) Mo or W and (c) Co and/or Ni ormixtures thereof. The pH buffering agent, may be suitable be aninorganic salt, particularly alkali salts such as, for example,potassium hydroxide, sodium hydroxide, and potassium carbonate orammonia. In other embodiments, catalysts containing Pt or Pd may also beeffective poison-tolerant catalysts for use in the techniques describedherein. When mediating in situ catalytic reduction reaction processes,sulfided catalysts may be particularly well suited to form reactionproducts comprising a substantial fraction of glycols (e.g., C₂-C₆glycols) without producing excessive amounts of the correspondingmonohydric alcohols. Although poison-tolerant catalysts, particularlysulfided catalysts, may be well suited for forming glycols from solublecarbohydrates, it is to be recognized that other types of catalysts,which may not necessarily be poison-tolerant, may also be used toachieve a like result in alternative embodiments. As will be recognizedby one having ordinary skill in the art, various reaction parameters(e.g., temperature, pressure, catalyst composition, introduction ofother components, and the like) may be modified to favor the formationof a desired reaction product. Given the benefit of the presentdisclosure, one having ordinary skill in the art will be able to altervarious reaction parameters to change the product distribution obtainedfrom a particular catalyst and set of reactants.

In some embodiments, slurry catalysts suitable for use in the methodsdescribed herein may be sulfided by dispersing a slurry catalyst in afluid phase and adding a sulfiding agent thereto. Suitable sulfidingagents may include, for example, organic sulfoxides (e.g., dimethylsulfoxide), hydrogen sulfide, salts of hydrogen sulfide (e.g., NaSH),and the like. In some embodiments, the slurry catalyst may beconcentrated in the fluid phase after sulfiding, and the concentratedslurry may then be distributed in the cellulosic biomass solids usingfluid flow. Illustrative techniques for catalyst sulfiding that may beused in conjunction with the methods described herein are described inUnited States Patent Application Publication US20100236988 andincorporated herein by reference in its entirety.

In various embodiments, slurry catalysts used in conjunction with themethods described herein may have a particulate size of about 250microns or less. In some embodiments, the slurry catalyst may have aparticulate size of about 100 microns or less, or about 10 microns orless. In some embodiments, the minimum particulate size of the slurrycatalyst may be about 1 micron. In some embodiments, the slurry catalystmay comprise catalyst fines in the processes described herein.

Catalysts that are not particularly poison-tolerant may also be used inconjunction with the techniques described herein. Such catalysts mayinclude, for example, Ru, Pt, Pd, or compounds thereof disposed on asolid support such as, for example, Ru on titanium dioxide or Ru oncarbon. Although such catalysts may not have particular poisontolerance, they may be regenerable, such as through exposure of thecatalyst to water at elevated temperatures, which may be in either asubcritical state or a supercritical state.

In some embodiments, the catalysts used in conjunction with theprocesses described herein may be operable to generate molecularhydrogen. For example, in some embodiments, catalysts suitable foraqueous phase reforming (i.e., APR catalysts) may be used. Suitable APRcatalysts may include, for example, catalysts comprising Pt, Pd, Ru, Ni,Co, or other Group VIII metals alloyed or modified with Re, Mo, Sn, orother metals such as described in United States Patent PublicationUS2008/0300435 and incorporated herein by reference in its entirety.

In some embodiments, the alcoholic component formed from the cellulosicbiomass solids may be further reformed into a biofuel. Reforming thealcoholic component into a biofuel or other material may comprise anycombination and sequence of further hydrogenolysis reactions and/orhydrogenation reactions, condensation reactions, isomerizationreactions, oligomerization reactions, hydrotreating reactions,alkylation reactions, dehydration reactions, desulfurization reactions,and the like. The subsequent conversion reactions may be catalytic ornon-catalytic. In some embodiments, an initial operation of downstreamconversion may comprise a condensation reaction, often conducted in thepresence of a condensation catalyst, in which the alcoholic component ora product derived therefrom is condensed with another molecule to form ahigher molecular weight compound. As used herein, the term “condensationreaction” will refer to a chemical transformation in which two or moremolecules are coupled with one another to form a carbon-carbon bond in ahigher molecular weight compound, usually accompanied by the loss of asmall molecule such as water or an alcohol. An illustrative condensationreaction is the Aldol condensation reaction, which will be familiar toone having ordinary skill in the art. Additional disclosure regardingcondensation reactions and catalysts suitable for promoting condensationreactions is provided hereinbelow.

In some embodiments, methods described herein may further compriseperforming a condensation reaction on the alcoholic component or aproduct derived therefrom. In various embodiments, the condensationreaction may take place at a temperature ranging between about 5° C. andabout 500° C. The condensation reaction may take place in a condensedphase (e.g., a liquor phase) or in a vapor phase. For condensationreactions taking place in a vapor phase, the temperature may rangebetween about 75° C. and about 500° C., or between about 125° C. andabout 450° C. For condensation reactions taking place in a condensedphase, the temperature may range between about 5° C. and about 475° C.,or between about 15° C. and about 300° C., or between about 20° C. andabout 250° C.

Each reactor vessel preferably includes an inlet and an outlet adaptedto remove the product stream from the vessel or reactor. In someembodiments, the vessel in which at least some digestion occurs mayinclude additional outlets to allow for the removal of portions of thereactant stream. In some embodiments, the vessel in which at least somedigestion occurs may include additional inlets to allow for additionalsolvents or additives.

In various embodiments, the higher molecular weight compound produced bythe condensation reaction may comprise ≧C₄ hydrocarbons. In some orother embodiments, the higher molecular weight compound produced by thecondensation reaction may comprise ≧C₆ hydrocarbons. In someembodiments, the higher molecular weight compound produced by thecondensation reaction may comprise C₄-C₃₀ hydrocarbons.

In some embodiments, the higher molecular weight compound produced bythe condensation reaction may comprise C₆-C₃₀ hydrocarbons. In stillother embodiments, the higher molecular weight compound produced by thecondensation reaction may comprise C₄-C₂₄ hydrocarbons, or C₆-C₂₄hydrocarbons, or C₄-C₁₈ hydrocarbons, or C₆-C₁₈ hydrocarbons, or C₄-C₁₂hydrocarbons, or C₆-C₁₂ hydrocarbons. As used herein, the term“hydrocarbons” refers to compounds containing both carbon and hydrogenwithout reference to other elements that may be present. Thus,heteroatom-substituted compounds are also described herein by the term“hydrocarbons.”

The particular composition of the higher molecular weight compoundproduced by the condensation reaction may vary depending on thecatalyst(s) and temperatures used for both the catalytic reductionreaction and the condensation reaction, as well as other parameters suchas pressure.

In some embodiments, a single catalyst may mediate the transformation ofthe alcoholic component into a form suitable for undergoing acondensation reaction as well as mediating the condensation reactionitself. In other embodiments, a first catalyst may be used to mediatethe transformation of the alcoholic component into a form suitable forundergoing a condensation reaction, and a second catalyst may be used tomediate the condensation reaction. Unless otherwise specified, it is tobe understood that reference herein to a condensation reaction andcondensation catalyst refers to either type of condensation process.Further disclosure of suitable condensation catalysts now follows.

In some embodiments, a single catalyst may be used to form a highermolecular weight compound via a condensation reaction. Without beingbound by any theory or mechanism, it is believed that such catalysts maymediate an initial dehydrogenation of the alcoholic component, followedby a condensation reaction of the dehydrogenated alcoholic component.Zeolite catalysts are one type of catalyst suitable for directlyconverting alcohols to condensation products in such a manner. Aparticularly suitable zeolite catalyst in this regard may be ZSM-5,although other zeolite catalysts may also be suitable.

In some embodiments, two catalysts may be used to form a highermolecular weight compound via a condensation reaction. Without beingbound by any theory or mechanism, it is believed that the first catalystmay mediate an initial dehydrogenation of the alcoholic component, andthe second catalyst may mediate a condensation reaction of thedehydrogenated alcoholic component. Like the single-catalyst embodimentsdiscussed previously above, in some embodiments, zeolite catalysts maybe used as either the first catalyst or the second catalyst. Again, aparticularly suitable zeolite catalyst in this regard may be ZSM-5,although other zeolite catalysts may also be suitable.

Various catalytic processes may be used to form higher molecular weightcompounds by a condensation reaction. In some embodiments, the catalystused for mediating a condensation reaction may comprise a basic site, orboth an acidic site and a basic site. Catalysts comprising both anacidic site and a basic site will be referred to herein asmulti-functional catalysts. In some or other embodiments, a catalystused for mediating a condensation reaction may comprise one or moremetal atoms. Any of the condensation catalysts may also optionally bedisposed on a solid support, if desired.

In some embodiments, the condensation catalyst may comprise a basiccatalyst comprising Li, Na, K, Cs, B, Rb, Mg, Ca, Sr, Si, Ba, Al, Zn,Ce, La, Y, Sc, Y, Zr, Ti, hydrotalcite, zinc-aluminate, phosphate,base-treated aluminosilicate zeolite, a basic resin, basic nitride,alloys or any combination thereof. In some embodiments, the basiccatalyst may also comprise an oxide of Ti, Zr, V, Nb, Ta, Mo, Cr, W, Mn,Re, Al, Ga, In, Co, Ni, Si, Cu, Zn, Sn, Cd, Mg, P, Fe, or anycombination thereof. In some embodiments, the basic catalyst maycomprise a mixed-oxide basic catalyst. Suitable mixed-oxide basiccatalysts may comprise, for example, Si—Mg—O, Mg—Ti—O, Y—Mg—O, Y—Zr—O,Ti—Zr—O, Ce—Zr—O, Ce—Mg—O, Ca—Zr—O, La—Zr—O, B—Zr—O, La—Ti—O, B—Ti—O,and any combination thereof. In some embodiments, the condensationcatalyst may further include a metal or alloys comprising metals suchas, for example, Cu, Ag, Au, Pt, Ni, Fe, Co, Ru, Zn, Cd, Ga, In, Rh, Pd,Ir, Re, Mn, Cr, Mo, W, Sn, Bi, Pb, Os, alloys and combinations thereof.Use of metals in the condensation catalyst may be desirable when adehydrogenation reaction is to be carried out in concert with thecondensation reaction. Basic resins may include resins that exhibitbasic functionality. The basic catalyst may be self-supporting oradhered to a support containing a material such as, for example, carbon,silica, alumina, zirconia, titania, vanadia, ceria, nitride, boronnitride, a heteropolyacid, alloys and mixtures thereof.

In some embodiments, the condensation catalyst may comprise ahydrotalcite material derived from a combination of MgO and Al₂O₃. Insome embodiments, the condensation catalyst may comprise a zincaluminate spinel formed from a combination of ZnO and Al₂O₃. In stillother embodiments, the condensation catalyst may comprise a combinationof ZnO, Al₂O₃, and CuO. Each of these materials may also contain anadditional metal or alloy, including those more generally referencedabove for basic condensation catalysts. In more particular embodiments,the additional metal or alloy may comprise a Group 10 metal such Pd, Pt,or any combination thereof.

In some embodiments, the condensation catalyst may comprise a basiccatalyst comprising a metal oxide containing, for example, Cu, Ni, Zn,V, Zr, or any mixture thereof. In some or other embodiments, thecondensation catalyst may comprise a zinc aluminate containing, forexample, Pt, Pd, Cu, Ni, or any mixture thereof.

In some embodiments, the condensation catalyst may comprise amulti-functional catalyst having both an acidic functionality and abasic functionality. Such condensation catalysts may comprise ahydrotalcite, a zinc-aluminate, a phosphate, Li, Na, K, Cs, B, Rb, Mg,Si, Ca, Sr, Ba, Al, Ce, La, Sc, Y, Zr, Ti, Zn, Cr, or any combinationthereof. In further embodiments, the multi-functional catalyst may alsoinclude one or more oxides from the group of Ti, Zr, V, Nb, Ta, Mo, Cr,W, Mn, Re, Al, Ga, In, Fe, Co, Ir, Ni, Si, Cu, Zn, Sn, Cd, P, and anycombination thereof. In some embodiments, the multi-functional catalystmay include a metal such as, for example, Cu, Ag, Au, Pt, Ni, Fe, Co,Ru, Zn, Cd, Ga, In, Rh, Pd, Ir, Re, Mn, Cr, Mo, W, Sn, Os, alloys orcombinations thereof. The basic catalyst may be self-supporting oradhered to a support containing a material such as, for example, carbon,silica, alumina, zirconia, titania, vanadia, ceria, nitride, boronnitride, a heteropolyacid, alloys and mixtures thereof.

In some embodiments, the condensation catalyst may comprise a metaloxide containing Pd, Pt, Cu or Ni. In still other embodiments, thecondensation catalyst may comprise an aluminate or a zirconium metaloxide containing Mg and Cu, Pt, Pd or Ni. In still other embodiments, amulti-functional catalyst may comprise a hydroxyapatite (HAP) combinedwith one or more of the above metals.

In some embodiments, the condensation catalyst may also include azeolite and other microporous supports that contain Group IA compounds,such as Li, Na, K, Cs and Rb. Preferably, the Group IA material may bepresent in an amount less than that required to neutralize the acidicnature of the support. A metal function may also be provided by theaddition of group VIIIB metals, or Cu, Ga, In, Zn or Sn. In someembodiments, the condensation catalyst may be derived from thecombination of MgO and Al₂O₃ to form a hydrotalcite material. Anothercondensation catalyst may comprise a combination of MgO and ZrO₂, or acombination of ZnO and Al₂O₃. Each of these materials may also containan additional metal function provided by copper or a Group VIIIB metal,such as Ni, Pd, Pt, or combinations of the foregoing.

The condensation reaction mediated by the condensation catalyst may becarried out in any reactor of suitable design, includingcontinuous-flow, batch, semi-batch or multi-system reactors, withoutlimitation as to design, size, geometry, flow rates, and the like. Thereactor system may also use a fluidized catalytic bed system, a swingbed system, fixed bed system, a moving bed system, or a combination ofthe above. In some embodiments, bi-phasic (e.g., liquid-liquid) andtri-phasic (e.g., liquid-liquid-solid) reactors may be used to carry outthe condensation reaction.

In some embodiments, an acid catalyst may be used to optionallydehydrate at least a portion of the reaction product. Suitable acidcatalysts for use in the dehydration reaction may include, but are notlimited to, mineral acids (e.g., HCl, H₂SO₄), solid acids (e.g.,zeolites, ion-exchange resins) and acid salts (e.g., LaCl₃). Additionalacid catalysts may include, without limitation, zeolites, carbides,nitrides, zirconia, alumina, silica, aluminosilicates, phosphates,titanium oxides, zinc oxides, vanadium oxides, lanthanum oxides, yttriumoxides, scandium oxides, magnesium oxides, cerium oxides, barium oxides,calcium oxides, hydroxides, heteropolyacids, inorganic acids, acidmodified resins, base modified resins, and any combination thereof. Insome embodiments, the dehydration catalyst may also include a modifier.Suitable modifiers may include, for example, La, Y, Sc, P, B, Bi, Li,Na, K, Rb, Cs, Mg, Ca, Sr, Ba, and any combination thereof. Themodifiers may be useful, inter alia, to carry out a concertedhydrogenation/dehydrogenation reaction with the dehydration reaction. Insome embodiments, the dehydration catalyst may also include a metal.Suitable metals may include, for example, Cu, Ag, Au, Pt, Ni, Fe, Co,Ru, Zn, Cd, Ga, In, Rh, Pd, Ir, Re, Mn, Cr, Mo, W, Sn, Os, alloys, andany combination thereof. The dehydration catalyst may beself-supporting, supported on an inert support or resin, or it may bedissolved in a fluid.

Various operations may optionally be performed on the alcoholiccomponent prior to conducting a condensation reaction. In addition,various operations may optionally be performed on a fluid phasecontaining the alcoholic component, thereby further transforming thealcoholic component or placing the alcoholic component in a form moresuitable for taking part in a condensation reaction. These optionaloperations are now described in more detail below.

As described above, one or more liquid phases may be present whendigesting cellulosic biomass solids. Particularly when cellulosicbiomass solids are fed continuously or semi-continuously to thehydrothermal (hydrocatalytic) digestion unit, digestion of thecellulosic biomass solids may produce multiple liquid phases in thehydrothermal digestion unit. The liquid phases may be immiscible withone another, or they may be at least partially miscible with oneanother. In some embodiments, the one or more liquid phases may comprisea phenolics liquid phase comprising lignin or a product formedtherefrom, an aqueous phase comprising the alcoholic component, a lightorganics phase, or any combination thereof. The alcoholic componentbeing produced from the cellulosic biomass solids may be partitionedbetween the one or more liquid phases, or the alcoholic component may belocated substantially in a single liquid phase. For example, thealcoholic component being produced from the cellulosic biomass solidsmay be located predominantly in an aqueous phase (e.g., an aqueous phasedigestion solvent), although minor amounts of the alcoholic componentmay be partitioned to the phenolics liquid phase or a light organicsphase. In various embodiments, the slurry catalyst may accumulate in thephenolics liquid phase as it forms, thereby complicating the return ofthe slurry catalyst to the cellulosic biomass solids in the mannerdescribed above. Alternative configurations for distributing slurrycatalyst particulates in the cellulosic biomass solids when excessivecatalyst accumulation in the phenolics liquid phase has occurred aredescribed hereinafter.

Accumulation of the slurry catalyst in the phenolics liquid phase may,in some embodiments, be addressed by conveying this phase and theaccumulated slurry catalyst therein to the same location where a fluidphase digestion medium is being contacted with cellulosic biomasssolids. The fluid phase digestion medium and the phenolics liquid phasemay be conveyed to the cellulosic biomass solids together or separately.Thusly, either the fluid phase digestion medium and/or the phenolicsliquid phase may motively return the slurry catalyst back to thecellulosic biomass solids such that continued stabilization of solublecarbohydrates may take place. In some embodiments, at least a portion ofthe lignin in the phenolics liquid phase may be depolymerized before orwhile conveying the phenolics liquid phase for redistribution of theslurry catalyst. At least partial depolymerization of the lignin in thephenolics liquid phase may reduce the viscosity of this phase and makeit easier to convey. Lignin depolymerization may take place chemicallyby hydrolyzing the lignin (e.g., with a base) or thermally by heatingthe lignin to a temperature of at least about 250° C. in the presence ofmolecular hydrogen and the slurry catalyst. Further details regardinglignin depolymerization and the use of viscosity monitoring as a meansof process control are described in commonly owned United StatesPublished Patent Application US20140117275 and incorporated herein byreference in its entirety.

After forming the alcoholic component from the cellulosic biomasssolids, at least a portion of the alcoholic component may be separatedfrom the cellulosic biomass solids and further processed by performing acondensation reaction thereon, as generally described above. Processingof the alcoholic component that has partitioned between various liquidphases may take place with the phases separated from one another, orwith the liquid phases mixed together. For example, in some embodiments,the alcoholic component in a fluid phase digestion medium may beprocessed separately from a light organics phase. In other embodiments,the light organics phase may be processed concurrently with the fluidphase digestion medium.

Optionally, the fluid phase digestion medium containing the alcoholiccomponent may be subjected to a second catalytic reduction reactionexternal to the cellulosic biomass solids, if needed, for example, toincrease the amount of soluble carbohydrates that are converted into thealcoholic component and/or to further reduce the degree of oxygenationof the alcoholic components that are formed. For example, in someembodiments, a glycol or more highly oxygenated alcohol may betransformed into a monohydric alcohol by performing a second catalyticreduction reaction. The choice of whether to perform a condensationreaction on a monohydric alcohol or a glycol may be based on a number offactors, as discussed in more detail below, and each approach maypresent particular advantages.

In some embodiments, a glycol produced from the cellulosic biomasssolids may be fed to the condensation catalyst. Although glycols may beprone to coking when used in conjunction with condensation catalysts,particularly zeolite catalysts, the present inventors found the degreeof coking to be manageable in the production of higher molecular weightcompounds. Approaches for producing glycols from cellulosic biomasssolids and feeding the glycols to a condensation catalyst are describedin commonly owned United States Published Patent ApplicationUS20140121420 and incorporated herein by reference in its entirety.

In some embodiments, a phenolics liquid phase formed from the cellulosicbiomass solids may be further processed. Processing of the phenolicsliquid phase may facilitate the catalytic reduction reaction beingperformed to stabilize soluble carbohydrates. In addition, furtherprocessing of the phenolics liquid phase may be coupled with theproduction of dried glycols or dried monohydric alcohols for feeding toa condensation catalyst. Moreover, further processing of the phenolicsliquid phase may produce methanol and phenolic compounds fromdegradation of the lignin present in the cellulosic biomass solids,thereby increasing the overall weight percentage of the cellulosicbiomass solids that may be transformed into useful materials. Finally,further processing of the phenolics liquid phase may improve thelifetime of the slurry catalyst.

These liquid phases or fluid phases can be used to remove water in thepretreatment as organic solvent, in the third contact zone, and thus beavailable for further processing

Various techniques for processing a phenolics liquid phase produced fromcellulosic biomass solids are described in commonly owned United StatesPublished Patent Applications US20140121419, US20140117277, andUS20140121418 and incorporated herein by reference in its entirety. Asdescribed therein, in some embodiments, the viscosity of the phenolicsliquid phase may be reduced in order to facilitate conveyance orhandling of the phenolics liquid phase. As further described therein,deviscosification of the phenolics liquid phase may take place bychemically hydrolyzing the lignin and/or heating the phenolics liquidphase in the presence of molecular hydrogen (i.e., hydrotreating) todepolymerize at least a portion of the lignin present therein in thepresence of accumulated slurry catalyst. Deviscosification of thephenolics liquid phase may take place before or after separation of thephenolics liquid phase from one or more of the other liquid phasespresent, and thermal deviscosification may be coupled to the reaction orseries of reactions used to produce the alcoholic component from thecellulosic biomass solids. Moreover, after deviscosification of thephenolics liquid phase, the slurry catalyst may be removed therefrom.The catalyst may then be regenerated, returned to the cellulosic biomasssolids, or any combination thereof.

In some embodiments, heating of the cellulosic biomass solids and thefluid phase digestion medium to form soluble carbohydrates and aphenolics liquid phase may take place while the cellulosic biomasssolids are in a pressurized state. As used herein, the term “pressurizedstate” refers to a pressure that is greater than atmospheric pressure (1bar). Heating a fluid phase digestion medium in a pressurized state mayallow the normal boiling point of the digestion solvent to be exceeded,thereby allowing the rate of hydrothermal digestion to be increasedrelative to lower temperature digestion processes. In some embodiments,heating the cellulosic biomass solids and the fluid phase digestionmedium may take place at a pressure of at least about 30 bar. In someembodiments, heating the cellulosic biomass solids and the fluid phasedigestion medium may take place at a pressure of at least about 60 bar,or at a pressure of at least about 90 bar. In some embodiments, heatingthe cellulosic biomass solids and the fluid phase digestion medium maytake place at a pressure ranging between about 30 bar and about 430 bar.In some embodiments, heating the cellulosic biomass solids and the fluidphase digestion medium may take place at a pressure ranging betweenabout 50 bar and about 330 bar, or at a pressure ranging between about70 bar and about 130 bar, or at a pressure ranging between about 30 barand about 130 bar.

To facilitate a better understanding of the present invention, thefollowing examples of preferred embodiments are given. In no way shouldthe following examples be read to limit, or to define, the scope of theinvention.

ILLUSTRATIVE EXAMPLES Example 1 Trickle Bed Acid Wash

A 25-mm inside diameter by 350-mm glass chromatography column was packedwith 44.5 grams of southern pine (39.5% moisture), filling 180milliliters of bed volume. An acidic treatment solution of 1 wt %sulfuric acid in deionized water was prepared. Acid wash was poured intothe top of the bed in slugs of 17.4, 14.7, 14.8, and 15.2 grams, thetotal of which comprised 34% of the volume of the bed. 33 grams oftreatment effluent were collected, and recycled ten times by pouringback into the top of the bed to effect another contacting cycle, and8-15 minute intervals. 24.9 grams were collected after ten recycles.

The effluent acid treatment was analyzed for metals via plasma emissionspectroscopy. Results (Table 1) show removal of calcium, potassium,magnesium, as well as transition metals manganese and iron via the acidwash trickle bed treatment. Silicon from silica impurity was alsoremoved by the wash procedure, among other metals removed.

Manganese removal corresponded to an estimated 46% of that present inthe initial wood sample, using an acidic effluent treatment that wasonly 15% of the bed volume of the biomass charged. This examples showsthe efficiency of trickle bed contacting, in removal of impurities usinga water volume that is only a fraction of the volume of the biomass bed.

TABLE 1 Metals Removal by Acid Wash in Trickle bed mode ppm wt in acidELEMENT/RESULT effluent Nickel 0.3 Cadmium <1 Zinc 2 Silicon 6.0 Boron 2Phosphorous 4 Manganese 28 Magnesium 94 Molybdenum <0.1 Vanadium <0.1Titanium 0.1 Copper 1 Cobalt 0.1 Aluminum 3 Lead <1 Iron 1 Potassium 145Sodium 41 Chromium 0.1 Calcium 278

Example 2 Trickle Bed Base Wash

A 25-mm inside diameter by 350-mm glass chromatography column was packedwith 30.1 grams of southern pine (39.5% moisture) to a height of 240 mm,filling 118 milliliters of bed volume. 40 grams of 1N KOH were pouredinto the bed at the top, and allowed to drain for 30 minute. Theeffluent was collected and recycled 10 times, producing 9.98 grams ofeffluent that were analyzed by ion chromatography for chlorides andphosphates. The base wash effluent was found to contain 20.4 ppmchloride and 25.1 ppm phosphate, removed by the trickle bed treatmentprocess.

The chloride concentration was 33% higher than the maximum observed intreatments using a larger amount of base, for a wood bed fully immersedin aqueous base solution. Despite producing a final wash that was only8% of a bed volume, nearly 16% of the chlorine present on the wood wasremoved via recycle contacting. Additional chloride and phosphateremoval is expected for additional base washing cycles using fresh basetreatment.

This example shows the high efficiency in use of trickle bed contacting,where a small volume of aqueous treatment can remove substantialconcentrations of impurities from biomass, thus minimizing the waterrequired for pretreatment.

What is claims is:
 1. A method for selective removal of at least aportion of detrimental metals and their anions from a detrimentalspecies-containing cellulosic biomass solids comprising: a. providing afirst portion of cellulosic biomass solids being contacted by a firstdispersed or semi-continuous liquid phase and first continuous gas phaseat a temperature in the range of about 0° C. to about 60° C. in a firstcontact zone wherein the liquid phase comprises acid solution having apH of at most 4 wherein the flux of the first liquid phase is at least 1kg/(m²s); b. providing said first dispersed or semi-continuous liquidphase treated cellulosic biomass solids being contacted by a seconddispersed or semi-continuous liquid phase and second continuous gasphase at a temperature in the range of about 0° C. to about 60° C. in asecond contact zone wherein the liquid phase comprises an aqueoussolution having a pH of at least 5 wherein the flux of the second liquidphase is at least 1 kg/(m²s); c. removing the first dispersed orsemi-continuous liquid phase from the first contact zone as an acidiceffluent; d. recovering the second dispersed or semi-continuous liquidphase from the second contact zone as aqueous effluent; e. recycling atleast a portion of the aqueous effluent as a portion of the liquid phasein the first contact zone; f. transferring at least a portion of saidsecond dispersed or semi-continuous liquid phase treated cellulosicbiomass solids to a digestion and/or reaction zone.
 2. The method ofclaim 1 wherein the first contact zone and the second contact zone arein one vessel.
 3. The method of claim 1 wherein the first contact zoneand the second contact zone are in separate vessels.
 4. The method ofclaim 1 wherein both first liquid phase and second liquid phase flowdownward.
 5. The method of claim 4 wherein the first gas phase is staticgas blanket to maintain pressure.
 6. The method of claim 4 wherein thefirst gas phase is flowing concurrently with the first liquid phase. 7.The method of claim 4 wherein the first gas phase is flowingcounter-currently with the first liquid phase.
 8. The method of claim 1wherein the biomass and the liquid phase is flowing counter-currently.9. The method of claim 1 wherein the first gas phase and the second gasphase is the same.
 10. The method of claim 1 wherein the flux of thefirst liquid phase is at least 3 kg/(m²s).
 11. The method of claim 1wherein the flux of the second liquid phase is at least 3 kg/(m²s). 12.The method of claim 1 wherein the acidic solution comprises an inorganicacid.
 13. The method of claim 1 wherein the inorganic acid is selectedfrom the group consisting of sulfuric acid, phosphoric acid,hydrochloric acid, and nitric acid.
 14. The method of claim 13 whereinthe inorganic acid is present in an amount of 0.01 wt % to 2 wt %. 15.The method of claim 14 wherein the inorganic acid is sulfuric acid. 16.The method of claim 15 wherein the sulfuric acid is present in an amountof 0.01 wt % to 1 wt %.
 17. The method of claim 14 wherein the inorganicacid is a phosphoric acid.
 18. The method of claim 17 wherein thephosphoric acid is present in an amount of 0.01 wt % to 2 wt %.
 19. Themethod of claim 14 wherein the inorganic acid is a nitric acid.
 20. Themethod of claim 19 wherein the nitric acid is present in an amount of0.01 wt % to 1 wt %.
 21. The method of claim 1 wherein the acidicsolution comprises a carboxylic acid.
 22. The method of claim 21 whereinthe carboxylic acid is selected from the group consisting of aceticacid, levulinic acid, lactic acid, formic acid, propionic acid, andmixtures thereof.
 23. The method of claim 21 wherein the carboxylic acidis present in an amount of 0.1 wt % to 5 wt %.
 24. The method of claim21 wherein the carboxylic acid is acetic acid.
 25. The method of claim24 wherein the acetic acid is present in an amount of 0.1 wt % to 2.5 wt%.
 26. The method of claim 1 wherein, in the digestion and/or reactionzone, the treated cellulosic biomass is contacted with a hydrothermalhydrocatalytic catalyst in the presence of hydrogen in the presence of adigestion solvent thereby producing an intermediate oxygenated productstream comprising oxygenated hydrocarbons and water; and at least aportion of the water is separated and recycled to form at least aportion of the aqueous solution.
 27. The method of claim 1 wherein, inthe digestion and/or reaction zone, the treated cellulosic biomass iscontacted with a hydrothermal hydrocatalytic catalyst in the presence ofhydrogen in the presence of a digestion solvent thereby producing anintermediate oxygenated product stream; at least a portion of theoxygenated intermediate product stream is converted to a hydrocarbonproduct stream comprising hydrocarbons and water; and at least a portionof the water is separated and recycled to form at least a portion of theaqueous solution.
 28. The method of claim 27 wherein, the oxygenatedintermediate product steam comprises oxygenated hydrocarbons and water,and at least a portion of the water is separated and recycled to form atleast a portion of the aqueous solution.
 29. The method of claim 1wherein the aqueous solution is in-situ generated.
 30. The method ofclaim 1 wherein the gas is selected from the group consisting of air,hydrogen, nitrogen, steam, organic vapors, and mixtures thereof.
 31. Themethod of claim 1 wherein the gas is pressurized up to 100 bar(preferable ambient to 10 bar).
 32. The method of claim 1 furthercomprising passing a gas and/or an organic solvent through said seconddispersed or semi-continuous liquid phase treated cellulosic biomassprior to transferring to a digestion and/or reaction zone.
 33. Themethod of claim 26 further comprising passing a gas and/or an organicsolvent through said second dispersed or semi-continuous liquid phasetreated cellulosic biomass prior to transferring to a digestion and/orreaction zone.
 34. The method of claim 25 wherein the organic solvent isthe digestion solvent.
 35. The method of claim 19 further comprisingpassing a gas and/or an organic solvent through said second dispersed orsemi-continuous liquid phase treated cellulosic biomass prior totransferring to a digestion and/or reaction zone.
 36. The method ofclaim 32 wherein the organic solvent is the digestion solvent.
 37. Themethod of claim 33 wherein the organic solvent is the digestion solvent.38. The method of claim 1 wherein the loss of carbohydrate from thewashing is less than 10% by weight, based on the carbohydrates presentin the biomass (dry basis).
 39. A method for selective removal of atleast a portion of detrimental metals and their anions from adetrimental species-containing cellulosic biomass solids comprising: a.providing a first portion of cellulosic biomass solids being contactedby a first dispersed or semi-continuous liquid phase and firstcontinuous gas phase at a temperature in the range of about 0° C. toabout 60° C. in a first contact zone wherein the liquid phase comprisesacid solution having a pH of at most 4 wherein the flux of the firstliquid phase is at least 1 kg/(m²s); b. providing said first dispersedor semi-continuous liquid phase treated cellulosic biomass solids beingcontacted by a second dispersed or semi-continuous liquid phase andsecond continuous gas phase at a temperature in the range of about 0° C.to about 60° C. in a second contact zone wherein the liquid phasecomprises an aqueous solution having a pH of at least 5 wherein the fluxof the second liquid phase is at least 1 kg/(m²s); c. providing saidsecond dispersed or semi-continuous liquid phase treated cellulosicbiomass solids being contacted by a third dispersed or semi-continuousliquid phase and third continuous gas phase at a temperature in therange of about 0° C. to about 60° C. in a third contact zone wherein thethird liquid phase comprises base solution having a pH of greater than 9wherein the flux of the third liquid phase is at least 1 kg/(m²s); d.providing said third dispersed or semi-continuous liquid phase treatedcellulosic biomass being contacted by a fourth dispersed orsemi-continuous liquid phase and fourth continuous gas phase at atemperature in the range of about 0° C. to about 60° C. in a fourthcontact zone wherein the liquid phase comprises an aqueous solutionhaving a pH of at most 8 wherein the flux of the fourth liquid phase isat least 1 kg/(m²s); e. removing the first dispersed or semi-continuousliquid phase from the first contact zone as an acidic effluent; f.recovering the second dispersed or semi-continuous liquid phase from thesecond contact zone as first aqueous effluent; g. removing the thirddispersed or semi-continuous liquid phase from the third contact zone asa basic effluent; h. recovering the fourth dispersed or semi-continuousliquid phase from the fourth contact zone as second aqueous effluent; i.recycling at least a portion of the first aqueous effluent as a portionof the liquid phase in the first contact zone; j. recycling at least aportion of the second aqueous effluent as a portion of the liquid phasein the third contact zone; k. transferring at least a portion of saidfourth dispersed or semi-continuous liquid phase treated cellulosicbiomass solids to a digestion and/or reaction zone.
 40. The process ofclaim 39 wherein the base solution comprises a base selected frompotassium hydroxide, sodium hydroxide or ammonia.
 41. The method ofclaim 39 wherein the base solution comprises a base in an amount of lessthan 5 Normal and at least 0.01 Normal.
 42. The method of claim 39wherein the acidic solution comprises an inorganic acid or a carboxylicacid.
 43. The method of claim 42 wherein the inorganic acid is selectedfrom the group consisting of sulfuric acid, phosphoric acid,hydrochloric acid, and nitric acid.
 44. The method of claim 39 whereinthe loss of carbohydrate from the washing is less than 10% by weight,based on the carbohydrates present in the biomass (dry basis).
 45. Themethod of claim 39 further comprising passing a gas and/or an organicsolvent through said treated cellulosic biomass prior to transferring toa digestion and/or reaction zone.
 46. A method for selective removal ofat least a portion of detrimental metals and their anions from adetrimental species-containing cellulosic biomass solids comprising: a.providing a first portion of cellulosic biomass solids being contactedby a first dispersed or semi-continuous liquid phase and firstcontinuous gas phase at a temperature in the range of about 0° C. toabout 60° C. in a first contact zone wherein the liquid phase comprisesa base solution having a pH of greater than 9 wherein the flux of thefirst liquid phase is at least 1 kg/(m²s); b. providing said firstdispersed or semi-continuous liquid phase treated cellulosic biomasssolids being contacted by a second dispersed or semi-continuous liquidphase and second continuous gas phase at a temperature in the range ofabout 0° C. to about 60° C. in a second contact zone wherein the liquidphase comprises an aqueous solution having a pH of at most 8 wherein theflux of the second liquid phase is at least 1 kg/(m²s); c. providingsaid second dispersed or semi-continuous liquid phase treated cellulosicbiomass solids being contacted by a third dispersed or semi-continuousliquid phase and third continuous gas phase at a temperature in therange of about 0° C. to about 60° C. in a third contact zone wherein thethird liquid phase comprises an acid solution having a pH of at most 4wherein the flux of the third liquid phase is at least 1 kg/(m²s); d.providing said third dispersed or semi-continuous liquid phase treatedcellulosic biomass being contacted by a fourth dispersed orsemi-continuous liquid phase and fourth continuous gas phase at atemperature in the range of about 0° C. to about 60° C. in a fourthcontact zone wherein the liquid phase comprises an aqueous solutionhaving a pH of at least 5 wherein the flux of the fourth liquid phase isat least 1 kg/(m²s); e. removing the first dispersed or semi-continuousliquid phase from the first contact zone as an basic effluent; f.recovering the second dispersed or semi-continuous liquid phase from thesecond contact zone as first aqueous effluent; g. removing the thirddispersed or semi-continuous liquid phase from the third contact zone asan acidic effluent; h. recovering the fourth dispersed orsemi-continuous liquid phase from the fourth contact zone as secondaqueous effluent; i. recycling at least a portion of the first aqueouseffluent as a portion of the liquid phase in the first contact zone; j.recycling at least a portion of the second aqueous effluent as a portionof the liquid phase in the third contact zone; k. transferring at leasta portion of said fourth dispersed or semi-continuous liquid phasetreated cellulosic biomass solids to a digestion and/or reaction zone.47. The method of claim 46 wherein the base solution comprises a baseselected from potassium hydroxide, sodium hydroxide or ammonia.
 48. Themethod of claim 46 wherein the base solution comprises a base selectedfrom potassium hydroxide, sodium hydroxide or ammonia.
 49. The method ofclaim 46 wherein the acidic solution comprises an inorganic acid or acarboxylic acid.
 50. The method of claim 49 wherein the inorganic acidis selected from the group consisting of sulfuric acid, phosphoric acid,hydrochloric acid, and nitric acid.
 51. The method of claim 46 whereinthe loss of carbohydrate from the washing is less than 10% by weight,based on the carbohydrates present in the biomass (dry basis).
 52. Themethod of claim 46 further comprising passing a gas and/or an organicsolvent through said treated cellulosic biomass prior to transferring toa digestion and/or reaction zone.